# Quantum Inequality Restrictions on Negative Energy Densities in Curved Spacetimes

@article{Pfenning1998QuantumIR, title={Quantum Inequality Restrictions on Negative Energy Densities in Curved Spacetimes}, author={Michael John Pfenning and L H Ford}, journal={arXiv: General Relativity and Quantum Cosmology}, year={1998} }

In quantum field theory, there exist states in which the expectation value of the energy density for a quantized field is negative. These negative energy densities lead to several problems such as the failure of the classical energy conditions, the production of closed timelike curves and faster than light travel, violations of the second law of thermodynamics, and the possible production of naked singularities. Although quantum field theory introduces negative energies, it also provides…

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